1. Field of the Invention
The invention relates to a heating apparatus for a fluid which is used as auxiliary heating means for a fluid such as an engine cooling water used for improving a starting performance of an engine for various kinds of vehicles mainly such as an automotive vehicle having a diesel engine and a gasoline engine as a power source at a time of a cold weather and a severe cold weather and heating a cabin of various kinds of vehicles including an electric vehicle and various kinds of ships, is used for pre-heating and rapidly increasing a temperature (shortening a warming up time) an engine cooling water of an engine driven power generator, a welding machine, a compressor and a construction machine, and is used for an apparatus for force feeding a hot water while increasing a temperature, a heating device of an air conditioning apparatus and a drying device such as a hair dryer, and more particularly to an apparatus for heating a fluid without using a separate heat exchanger and force feeding the fluid by a rotationally driven pump mechanism.
2. Description of the Prior Arts
Conventionally, as an auxiliary heating source for a vehicle such as an automotive vehicle which is used for heating an engine cooling water at a starting time in a cold weather area, there has been known a viscous type heater (refer to Japanese Patent Unexamined Publication Nos. 2-246823, 9-254637, 9-66729 and 9-323530 and Japanese Utility Model Unexamined Publication No. 4-11716).
The viscous type heater is of the type which heats up a viscous fluid such as a silicone oil by shearing so as to exchange heat with a circulating water circulating within a water jacket and utilize for a heating source. The structure is made, for example, such that a heat generating chamber is formed in an inner portion of a housing, the water jacket is formed in an outer area of the heat generating chamber, a drive shaft is rotatably supported to the housing via a bearing apparatus, a rotor capable of rotating within the heat generating chamber is fixed to the drive shaft, a viscous fluid such as a silicone oil is sealed in a gap between a wall surface of the heat generating chamber and the rotor, and a circulating water is circulated so as to be taken into the water jacket from a water inlet port and be fed out to an external heating circuit from a water outlet port.
In this kind of viscous type heater assembled in the heating apparatus of the vehicle, since the rotor is rotated within the heat generating chamber when the drive shaft is driven by an engine, the viscous fluid generates heat due to shearing in the gap between the wall surface of the heat generating chamber and the outer surface of the rotor, the generated heat is exchanged with the circulating water within the water jacket, and the heated circulating water is used for heating the vehicle such as the engine cooling water in the heating circuit.
However, since the viscous type heater mentioned above can realize a compact size and a reduced cost in accordance with a simple structure, can secure a high reliability and safety in accordance with a frictionless non-contact type mechanism, and can automatically stop an operation in accordance with a temperature control when a water temperature is increased and the auxiliary heater is not necessary, there is a feature that a wasteful energy is not used. However, as well as an independent heat exchanging mechanism and heating circuit are required, a temperature of the silicone oil can not be increased sufficiently because a heat resistance of the silicone oil used as the viscous fluid is limited to about 240.degree. C., a lot of time is required before the silicone oil is mixed to be heated to a high temperature at a start time, and an amount of heat generated at a unit time tends to be gradually reduced in accordance that a shearing resistance is lowered due to a reduction of a viscosity when a temperature of the silicone oil is increased, so that there has been a problem that a quick heating effect can not be obtained at an engine cooled time. Accordingly, in particular, in the case of a cold district design vehicle mounting a diesel engine, the viscous type heater mentioned above is not sufficient in an efficiency, so that there has been desired an auxiliary heater installing an apparatus for force feeding the fluid while more quickly and efficiently increasing the temperature of the fluid to a high temperature.
Further, conventionally, a warm and hot air generating apparatus represented by an apparatus for force feeding a warm water while increasing a temperature thereof, a heating device of an air conditioning apparatus and a drying device such as a hair dryer is constituted by a heating source such as a heat exchanger and an electrically heating heater and a force feeding apparatus such as a blower, in which the heating source and the blower are arranged apart from each other at a desired distance. That is, the conventional warm and hot air generating apparatus is generally structured such that the blower is provided in front of the heating source, and an air fed from the blower is heated when passing through the heating source such as the electrically heating heater or warmed so as to be discharged. Here, in the case that the fluid is a liquid, it has been force fed by the pump after being heated by the heat exchanger or heated by the heat exchanger after being force fed by the pump.
However, in this kind of conventional heating and force feeding apparatus, there are the following disadvantages. (1) It is impossible to make the apparatus compact since the force feeding apparatus such as the heating source and the blower is essential, (2) in the case that the electric heating heater is used for the heating means for the air and the water, a heat resistance and a durability are deteriorated since the electric heating heater is weak against moisture and it costs high since it is necessary to insulate the heater, (3) the apparatus is not preferable in view of safety since there is a risk that the electric heating heater fires due to an overheat, and (4) the pump and the heat exchanger are required, and the heat exchanger requires a large exchanging calorie.